REGULATION OF HMG-COA REDUCTASE MRNA LEVELS

HMG-COA 还原酶 mRNA 水平的调节

• 批准号: 3335471
• 负责人: DAVID J SHAPIRO
• 金额: $ 9.2万
• 依托单位: UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN
• 依托单位国家: 美国
• 财政年份: 1978
• 资助国家: 美国
• 起止时间: 1978-03-01 至 1987-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3335471
• 关键词: HMG coA reductases; biological information processing; cholesterol analog; clone cells; complementary DNA; enzyme induction /repression; gene expression; genetic manipulation; genetic transcription; hypercholesterolemia; immunochemistry; liposomes; liver cells; messenger RNA; mevalonate; molecular cloning; monoclonal antibody; mutant; nucleic acid sequence; radiotracer; regulatory gene; sterols

3-hydroxy-3-methylglutaryl (HMG)-CoA reductase is a key regulatory enzyme in cholesterol, dolichol, ubiquinone, and isopentenyl adenosine biosynthesis. The molecular mechanisms through which sterols and non-sterol products derived from mevalonate regulate the level of HMG-CoA reductase, and of reductase mRNA, will be determined. HMG-CoA reductase cDNA and genomic clones will be isolated from wild type rat liver cells and used to determine HMG-CoA reductase is encoded by a single gene or a small gene family. We have established a simple model system for regulation of HMG-CoA reductase based on the water soluble cholesterol derivative methoxy polyoxyethyl (MPOE) cholesterol. The effect of MPOE cholesterol on reductase mRNA levels and on reductase gene transcription, nuclear RNA processing and degradation, and cytoplasmic mRNA stability will be determined. Biochemical experiments and available mutant cell lines will be used to determine whether oxygenated sterols (7-keto cholesterol) exhibit the same mode of actions as MPOE cholesterol. We will use similar techniques to determine whether non-sterol products derived from mevalonate regulate HMG-CoA reductase through the same mechanism as sterols. We shall investigate the possibility that HMG-CoA reductase is subject to multivalent regulation in which different end products of a biosynthetic pathway regulate expression of different members of a gene family. These studies should deepen our understanding of the molecular mechanism through which the level of HMG-CoA reductase, and ultimately the rate of cholesterol synthesis, are controlled. They will also provide a useful model for control of the level of cellular regulatory enzymes in mammalian systems.

3-羟基-3-甲基戊二酰（HMG）-COA还原酶是关键调节酶 在胆固醇，多利果醇，泛氨基酮和异戊烯基腺苷中 生物合成。 固醇和固醇和的分子机制 源自甲谷酸盐的非肉酚产品调节HMG-COA的水平 还将确定还原酶和还原酶mRNA。 HMG-COA还原酶cDNA和基因组克隆将从野生型中分离出来 大鼠肝细胞并用于确定HMG-COA还原酶由A编码 单基因或小基因家族。 我们已经建立了一个简单的模型系统，用于调节HMG-COA 基于水溶性胆固醇衍生物甲氧基的还原酶 多氧乙基（MPOE）胆固醇。 MPOE胆固醇对 还原酶mRNA水平和还原酶基因转录，核RNA 加工和降解以及细胞质mRNA稳定性将是 决定。 生化实验和可用的突变细胞系将用于 确定含氧固醇（7-酮胆固醇）是否表现出相同 作为MPOE胆固醇的作用方式。 我们将使用类似的技术 确定是否源自Mevalonate调节的非STEROL产品是否 HMG-COA还原酶通过与固醇相同的机制。 我们将 研究HMG-COA还原酶受到的可能性 多价法规，其中生物合成的不同最终产物 途径调节基因家族不同成员的表达。 这些研究应加深我们对分子机制的理解 通过该水平HMG-COA还原酶的水平，最终是 胆固醇合成是控制的。 他们还将提供有用的 控制哺乳动物中细胞调节酶水平的模型 系统。